Lithium batteries protection in low temperatures

Bart

Bart

Free Member
Joined
Jun 4, 2016
Posts
3,188
Likes collected
1,398
Location
Northern Ireland
Funster No
43,436
MH
Boxer L4H2 van build
Exp
Since 2016
In our MH conversion we have installed lithium batteries , but the other day I went out to work on the conversion and when I went to turn on the heater it never worked because the lithium had went into temperature protection mode , it had been set to 2degrees , so I changed it to 1 degree and everything was good , however this morning I went out and same thing again , so when I looked at the battery temp software it said -3 degrees , so I wasn't prepared to take a chance and adjust the temp protection lower to enable the batteries to work again , so I left the heat off.

So what temperature protection setting do other lithium users have their batteries set to , I'm especially interested in someone who lives full time in the van or anyone who encounters low temperatures while in the MH.
 
Ours have a discharge lower limit of -20, charging limit is 0, are you confusing the two?

Just to add though we don't full time but if we did the batteries would be less likely to see low temperatures that the way we use it now.
 
funflair said:
Ours have a discharge lower limit of -20, charging limit is 0, are you confusing the two?

Just to add though we don't full time but if we did the batteries would be less likely to see low temperatures that the way we use it now.
Click to expand...
My thoughts too, you should still be able to draw power well below zero just can't charge them.

I wouldn't risk charging at 1° if you have temperature sensing on the charger better set to cut off at 4°. The BMS is a last resort.
 
Which lithiums do you have installed and what BMS features does it have? As Lenny HB and Martin (funflair) have said, you seem to be referring to charge protection and that shouldn’t affect discharge ability.

Ian
 
This seems to be happening a fair bit at the moment ... Lithium batteries not operating now temp is below 0C.

Yes, they SHOULD be able to operate down to -20C but just refuse a charge below 0C. However it looks like either the BMSes of some makes may not have been configured correctly, or corners have have cut in the batteries build and internally the same wiring used all the way on the discharge AND charge cable, so when the charge is disabled, the discharge ends up being disabled as well. Not good and not right. (but not that surprising).

Bart said:
In our MH conversion we have installed lithium batteries , but the other day I went out to work on the conversion and when I went to turn on the heater it never worked because the lithium had went into temperature protection mode , it had been set to 2degrees , so I changed it to 1 degree and everything was good , however this morning I went out and same thing again , so when I looked at the battery temp software it said -3 degrees , so I wasn't prepared to take a chance and adjust the temp protection lower to enable the batteries to work again , so I left the heat off.

So what temperature protection setting do other lithium users have their batteries set to , I'm especially interested in someone who lives full time in the van or anyone who encounters low temperatures while in the MH.
Click to expand...
What brand of Battery (and BMS if you know it) have you got?

Subscribers  do not see these advertisements

 
Bart said:
In our MH conversion we have installed lithium batteries , but the other day I went out to work on the conversion and when I went to turn on the heater it never worked because the lithium had went into temperature protection mode , it had been set to 2degrees , so I changed it to 1 degree and everything was good , however this morning I went out and same thing again , so when I looked at the battery temp software it said -3 degrees , so I wasn't prepared to take a chance and adjust the temp protection lower to enable the batteries to work again , so I left the heat off.

So what temperature protection setting do other lithium users have their batteries set to , I'm especially interested in someone who lives full time in the van or anyone who encounters low temperatures while in the MH.
Click to expand...
i bought a battery from Fogstar that has a heating element built into the battery. i suspect a lot of batteries from other sources also do aswell, so those who venture into (or live in) colder climes, can use their batteries (charge and discharge) through different temperatures?

EDIT - please see comment from Lenny HB below !!

as part of a home battery project, i will be adding some sort of heat pad to the battery bank, possibly a vivarium type pad, powered by AC so i dont have to depend on the DC side to power it
 
Last edited:
MisterB said:
i bought a battery from Fogstar that has a heating element built into the battery. i suspect a lot of batteries from other sources also do aswell, so those who venture into (or live in) colder climes, can use their batteries (charge and discharge) though different temperatures?
Click to expand...
The heater only works on the charge cycle.
 
I had thought about an insulated cover for Lithium batteries to protect during winter months would it actually help ?
 
Thanks for all the fast replies , my bms units a Daly , but yes seems I am getting confused , I will change the discharge temp to -20 , 99% of the charging will be done by a renogy 60amp b2b charger , I'll have to see if it has a temp cut out on it ,so it doesn't charge at to low a temp. , As well as setting the charge temp at min zero in the bms

Subscribers  do not see these advertisements

 
Lenny HB said:
Insulation only slows the rate of cooling ultimately they will reach the same temperature.
Click to expand...
Hi Lenny, I use my van nearly every day so temp inside van only drops during night so doesn’t remain too cold for too long.
 
Otter Spotter said:
I had thought about an insulated cover for Lithium batteries to protect during winter months would it actually help ?
Click to expand...
I suppose only if the battery emitted any heat to keep in? If anything Id suggest Polystyrene ? maybe

Similar , I have mine in the hab area under seat where my inverter and a heat pipe goes, so tends to work fine in winter, esp if sat on drive with frost protection on.
 
Bart said:
In our MH conversion we have installed lithium batteries , but the other day I went out to work on the conversion and when I went to turn on the heater it never worked because the lithium had went into temperature protection mode , it had been set to 2degrees , so I changed it to 1 degree and everything was good , however this morning I went out and same thing again , so when I looked at the battery temp software it said -3 degrees , so I wasn't prepared to take a chance and adjust the temp protection lower to enable the batteries to work again , so I left the heat off.

So what temperature protection setting do other lithium users have their batteries set to , I'm especially interested in someone who lives full time in the van or anyone who encounters low temperatures while in the MH.
Click to expand...
I don't know if my ( cheap chinese ) lithium battery BMS has temperature protection as the battery is sealed with little detailed info on it specs being available.
I am relying on the charging devices that have temperature sensors to limit charging below zero.
Today is the first time since converting to a lifepo4 lithium when its been below zero and a sunny (uk) day.
I have a votronic mppt solar regulator and just one 120w panel. The battery was at -1.5c ( cheap temperature display with sensor taped to the -ve pole of the battery ). At 1 pm the battery was at 99% charged ( victron smart shunt display ) and I was surprised it was charging at 1.5A. Thought it would not be charging as the temp was below zero and the votronic temp sensor ( bolted also to the -ve terminal ) should stop any charging ?
The battery reached 100% even at just 1A or so for 2hrs or so whilst the sun lasted, The maximum voltage reached just 14v so you don't need 14.6v to fully charge.
As for the NE237, mine charges at 15 - 17 amps and gets quite warm ( possibly too warm )?
The NE237 has no temperature sensor so if the battery is below 0deg it must not be used. ( I have fitted an on/off switch in the 'kettle lead' cable ) and control it manually.
Its set on the Gell setting and charges the battery to a max of 14.35v ( never goes above this ) but the battery reaches 100% charge. This is confirmed by the battery charging current falling to below 0.5A and eventually settling at around 0.3A.
It is not a good idea the leave it on charge as when it falls to less than 1 amp charging relays start clicking in the NE237 and/or perhaps the battery BMS ? and the charger trips out until the mains ehu is disconnected and re-connected.
Don't know why it trips-out like this as the charging current is very low when it does it ?

I asked Apulijack about their modification of the NE237 to lithium profile and it was explained that the mod INCREASES the charging voltage !.They state that the lower 14.4v gel setting or the 14.7v lead will not fully charge a lifepo4 ( and will stress parts in the charger ? )
I am not convinced about this modification. It would be interesting to know what the Constant Current value and period is after the modification, also the max voltage and the float voltage at reaching 100% charge ( or does it switch off ) and at what voltage does charging begin again ?

I have found that the gel setting charges my 150ah lithium initially at 17A falling to 15A as it approaches 95% then slowing to 5A at 99% and dropping very rapidly to less than 1A as it reaches 100%. ( within a few minutes )
It would appear that once the battery reaches 14.35v and 100% charged the current drops almost to zero, but I dont know if this could overcharge or stress the battery if left on for long periods ?
If you research real world studies and experiments carried out by such as 'The off grid garage' on youtube you will see that charging at significantly below the 14.65v manufacturers maximum extends the life of battery but going over the max risks permanent damage.
Even charging at as low as 14v will charge to 100%, it *may* take longer. Higher voltages will drive larger currents ( and charge faster ) but can your Alternator/solar/Ehu charger produce perhaps 100A without damaging the wiring/alternator ?
( My 30A B-B draws somewhere around 35A -40A on its input.
Starting on a cold wet morning after discharging the lithium 25ah the evening/night before, occasionally causes the alternator belt to squeal as it tries to supply 40A ish over and above the load of the starter battery, lights, Fridge Freezer etc ).
Even at 14v my lithium is charging at 15A+ providing the charging source can supply that current. I my case the B-B can charge at 30A but the Fridge Freezer takes 15A as soon as the engine starts. My NE237 can only supply 17A and the solar less than 7A so whats the point in raising the charge voltage above 14.2 - 14.4v.
The one potential problem is the battery has a built-in BMS which limits discharge to 100A but also has crucial cell balancing and other safety functions.
I dont know if the balancing function has a minimum voltage before it starts doing its stuff as its sealed inside the battery and there is no interface to make changes or find this out ?
Perhaps a reason to opt for 14.4v charging if the charging device has different voltage settings ?

Another 'querk' of lithiums is that if the charging device, say solar, has limited choice of settings eg 14.6v bulk charge and 13.6v 'float' what happens typically is that before mid-day the battery reaches 100% at 14.55v on a sunny day. Battery charging ceases and the battery discharges with small loads during the rest of sunny afternoon, typically 3-7 ah before sundown.
So late afternoon top-up charging is lost because solar charging wont start again until the battery voltage falls to less than 13.5v.
( I plan to change the setting on The Votronic MPPT to another lithium profile 14.4v but with a 13.8v 'float' to see if it will restart charging at 13.6v to make up for small loads in the afternoon instead of shutting down until the next day ) ? not a quick change as the solar regulator is not easily accessible.

Compounding that afternoon loss of available solar charging is that my Votronic B-B unit has an automatic charging bridge that continues to trickle charge the start battery from the lithium at up to 1A until the lithium battery voltage falls to less than 13.4v loosing another few a/h's !
Sorry for the long read but if any lithium guru's can enlighten me further on these niggles it would be appreciated.
 
Tombola said:
I suppose only if the battery emitted any heat to keep in? If anything Id suggest Polystyrene ? maybe

Similar , I have mine in the hab area under seat where my inverter and a heat pipe goes, so tends to work fine in winter, esp if sat on drive with frost protection on.
Click to expand...
Been thinking what to do if we need to use the motorhome on a really cold morning. A good idea to run the heating the night before ?
The problem of low temperature with lithiums is with being charged below 0degC not discharging.
Just a thought... Lifepo4's generate heat internally ( just where you would need warming ) when being discharged.
So if you wanted to set off when the battery internals are below zero you could start discharging the battery, Say 10A - 20A load about 11/2 to 2 hrs before needing to set off and the internals of the battery would be warmed by this and it could then accept a charge.
Yes, you have lost 20 -30 a/h's but that discharged energy would be put back in an hour or less of driving, assuming you have a BtoB.
If you did the discharge with a fan assisted discharger place facing the battery the warm air could also be employed in assisting warming of the battery casing ?
 
Adriaadventure said:
I asked Apulijack about their modification of the NE237 to lithium profile and it was explained that the mod INCREASES the charging voltage !.They state that the lower 14.4v gel setting or the 14.7v lead will not fully charge a lifepo4 ( and will stress parts in the charger ? )
Click to expand...
For only a few quid more than Apuljack's price to mod you can buy a Victron 15 amp IP22 charger which has a lithium profile.

Subscribers  do not see these advertisements

 
There are BMS es with single channel/port, and dual channel/port. One controls the charge and the other controls the discarge. Early bms is single channel/port only, and all charge / discharge is controlled together like a switch. Dally made, and still makes single port bms. If you don’t have separate setting for charge/ discharge low temp cut of, is likely to be single port bms. If you lower the temp to enable discharging, make sure you don’t charge in the same time. Wait until temp raised enough to resume charging. Safe practice is resume charging above 5deg C. I have done it at 2 degC with very low current to get some heat in the battery.
 
Raul said:
There are BMS es with single channel/port, and dual channel/port. One controls the charge and the other controls the discarge. Early bms is single channel/port only, and all charge / discharge is controlled together like a switch. Dally made, and still makes single port bms. If you don’t have separate setting for charge/ discharge low temp cut of, is likely to be single port bms. If you lower the temp to enable discharging, make sure you don’t charge in the same time. Wait until temp raised enough to resume charging. Safe practice is resume charging above 5deg C. I have done it at 2 degC with very low current to get some heat in the battery.
Click to expand...
Thanks for that Raul, learnt a few things about BMS's.
Don't think mine has low temperature protection, it was minus 3 at the battery at 11:00 this morning and the battery was being charged at 0.2A by the low morning sun according to the smart shunt. I put a small load ( couple of led spot-lights ) to create a discharge of about 0.25A to stop charging and put the Alde on to raise the temp in MH to 5 deg for a couple of hours.
Perhaps I need to pull the fuse on the Votronic mppt if its going to be a frosty night to stop charging the following morning ?
I in your reply I don't understand what you meant by '' If you lower the temp to enable discharging, make sure you don’t charge in the same time ''.
Why would I lower the temp to enable discharging ? or did you not mean that.
 
It was meant for Bart, if you read his reply it makes sense.
Yours it’s another problem.
It seems that vortronic does not stop charging on low, despite having a sensor. Turn off charger if it’s going to be cold, or test the temp probe that works with the charger.
 
Lenny HB said:
For only a few quid more than Apuljack's price to mod you can buy a Victron 15 amp IP22 charger which has a lithium profile.
Click to expand...
And would be very different to the Apuljack in terms of settings. the LI-on setting on the IP22 is a voltage of 14.2V.

I have found with the various Lithiums I have tried, they are typically at 100% SOC by the time the voltage reaches 14.1V and I certianly would not want a charger with a "lithium" profile of over 14.7V! (and especially pay £150 odd for a charger I had to be modified with that change!!)
 
Last edited:
Raul said:
There are BMS es with single channel/port, and dual channel/port. One controls the charge and the other controls the discarge. Early bms is single channel/port only, and all charge / discharge is controlled together like a switch. Dally made, and still makes single port bms. If you don’t have separate setting for charge/ discharge low temp cut of, is likely to be single port bms. If you lower the temp to enable discharging, make sure you don’t charge in the same time. Wait until temp raised enough to resume charging. Safe practice is resume charging above 5deg C. I have done it at 2 degC with very low current to get some heat in the battery.
Click to expand...
Sorry for the late reply Raul, thanks for the info , both my BMS's are Dally and both around 1 year old and are bluetooth enabled, and when i am in the app for the BMS i am able to define separate temp parameters for both discharge and charge , i take it i don't have a single port version as i am able to define both discharge and charge temp parameters.

Subscribers  do not see these advertisements

 
Just picking up on this thread, as looking to switch to Lithium this year, looking at the Fogstars with inbuilt heater, I assume these only work whilst charging? how much power do they take? and on a cold but bright day like today, how would they work with Solar producing only 5-6 A? would the heater possibly use more than the solar can deliver?
 
The heater is triggered by the bms. It will disable charging, but you still can discharge. As soon as you put some charge the heater will take that to bring it up to temperature. When they warm enough, the charge will go to the battery. The heating pad can vary 1,2-3A. At least that’s how the KJ bms works, same as renogy and roamer. Fogstar uses two types if I’m not wrong, they use JBD and JK. You should ask their support all this details, they may even customise it to your needs. I had very good experience with fogstar before and after sale support.
 
Raul said:
The heater is triggered by the bms. It will disable charging, but you still can discharge. As soon as you put some charge the heater will take that to bring it up to temperature. When they warm enough, the charge will go to the battery. The heating pad can vary 1,2-3A. At least that’s how the KJ bms works, same as renogy and roamer. Fogstar uses two types if I’m not wrong, they use JBD and JK. You should ask their support all this details, they may even customise it to your needs. I had very good experience with fogstar before and after sale support.
Click to expand...
Interesting so it will use the charge to heat as opposed drain the battery? this time of year when we get cold days with limited sun it probably won't do much in the way of charging or even maintaining, (when the sun is low, where we store our van it is in partial shade) but given that we are looking at a 460ah battery probably, it should last a few months of drain, until the sun comes back.
 
It will last, we have 400ah on the van and and do charge as we use it. When it’s parked up I don’t worry. At the moment it’s at 70%, that should go few weeks for us.
 
Raul said:
It will last, we have 400ah on the van and and do charge as we use it. When it’s parked up I don’t worry. At the moment it’s at 70%, that should go few weeks for us.
Click to expand...
Thats the nice thing about having a massive battery backup, standby drain has negligible effect.

Subscribers  do not see these advertisements

 
I have 2 x 100 amp Transporter Lithium batteries, they will supply power down to minus 20 and an be charged from -4c not cheap but guaranteed for 10 year with a life expectancy of 15.
 
gerry mcg said:
that is what i did / have (y)
Click to expand...
Does this victron unit have a temperature probe to regulate charging when the lithium battery is at or below 0 deg C ?, and if so does it actually prevent charging at this temperature.
 
Adriaadventure said:
Does this victron unit have a temperature probe to regulate charging when the lithium battery is at or below 0 deg C ?, and if so does it actually prevent charging at this temperature.
Click to expand...
There are two revisions of the IP22 Charger mentioned
The older one has settings to configure temperature compensation, which you would use with Lead Acid Batteries, but you cannot set it to turn off at a set temperature, so is not suitable if you want a charger with a built-in disconnect.
The later one, which is what you will get if you buy new, can be configured to turn off at a low temp and also join in a VE Smart Network for more accurate and dynamic temperature info.
 
I’ve ready this thread with interest. I’m replacing my 95ah agm with a renology 170 ah probably. My schaudt unit does not have a lithium setting so I’m thinking an ip22 charger, but what ah rating. 20ah? Also, which b2b unit, temp controller etc plus anything else I should fit while I’m at it?
I also have a 200w solar panel and victron 75/15 mppt.

Subscribers  do not see these advertisements

 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Join us

Log in

Already a member? Log in here.

Latest journal entries

Back
Top